Brush rigging



W. J. MORRILL v BRUSH- RIGGING May 7, 1946.

Filed Dec. 25, 1942 Inventor- Wayne J. Mot-rill,

His Attorney.

Patented May 7, 1946 UNITED STATES PATENT OFFICE General Electric ComNew York pany, a corporation of Application December 23, 1942, SerialNo. 469,861

11 Claims.

My invention relates to brush riggings such as are used in connectionwith dynamo-electric machine current collectors.

An object of my invention is to provide an improved and simplified brushrigging.

Another object of my invention is to provide an improved brush riggingin which the brush and brush holder move as a unit relative to a currentcollector and the contact surface of the brush remains substantially thesame for all conditions of wear of the brush.

Further objects and advantages of my invention will become apparent andmy invention will be better understood from the following descriptionreferring to the accompanying drawing, and the features of novelty whichcharacterize my invention will be pointed out with particularity in theclaims annexed to and forming part of this specification.

In the drawing, Fig. 1 is an exploded perspective view of an embodimentof my improved brush rigging; Fig. 2 is a side elevational view, partlyin section, illustrating an assembly of the brush rigging shown in Fig.1; Fig. 3 is an exploded perspective view of a brush rigging providedwith another embodiment of my invention; Fig. 4 is an assembledperspective view of the brush rigging shown in Fig. 3; and Fig. 5 is aside elevational view, partly in section, of the brush rigging shown inFigs. 3 and 4.

Referring to the drawing, I have shown in Figs. 1 and 2 a brush riggingwhich includes a contact brush member formed of a graphitic element lhaving a Wearing contact lower portion with substantially parallelcurved opposite sides H and I2 formed on the same center of curvature.The contact brush element in is formed with a brush holder engagingportion l3 having opposite sides, one of which is formed by the side Hand the other of which is formed by a tapered side I 4 extending at anangle to the sides i l and I2 providing a substantially wedge shape tothe end brush holder engaging brush portion i3. A metal sheath I isarranged over the brush holder engaging portion of the brush member andis secured to the graphitic portion of the brush ill by a suitable rivetHi. This brush member is adapted to be supported by a brush holder andresiliently biased into contact with a current collector IT. The brushholder is provided with sides i8 which are held together by atransversely extending plate l9 having fastening tabs 20 which extendthrough openings formed in the sides 3 and which are upset to providerivet heads securing together the sides l8 and the transverse plate I9.

Each of the sides [8 of the brush holder is formed with an inturnedbrush engaging end element 2i. These elements 2| are arranged to engagethe brush at transversely spaced apart points on one side of the brushmember metal sheath I5. The transverse plate IQ of the brush holder isformed with spaced apart projections 22 and 23 adjacent the upper andlower ends thereof respectively, and these projections are formed on theplate l9 transversely thereof intermediate the brush engaging elements2! and are spaced longitudinally above and below the elements 21 toprovide for engagement of the brush member sheath i5 on the side thereofopposite the side M to provide brush engaging points spaced apartlongitudinally of the brush member and spaced transversely intermediatethe points of engagement of the brush with the elements 2| for wedgingthe brush member between the engaging elements on the opposite sidesthereof. This provides for a rigid support of the brush in the brushholder and prevents any relative movement therebetween. The brush memberand the brush holder are adapted to be biased resiliently as a unittowards the current collector I! by a resilient coil spring 24 which isprovided with an end portion 25 hooked over a stationary pin 26 andanother end portion 21 in engagement with an inturned end portion 28 ofthe transverse plate [9. The brush holder is pivotally supported on aspindle 29 adapted to extend through holes 30 in the brush holder sidesl8 and is provided with a head 3| for holding the brush holder on thespindle. The end of the spindle away from the head 3| is threaded toprovide for securing it to a suitable bracket for-pivotally supportingthe brush and brush holder about an axis 32 of the spindle 29 which liesin a plane indicated by the line 33 which is substantially tangent tothe current collector I! at the center of the contact of the brushmember with the current collector. The center of curvature of the sidesII and 12 of the brush element l0 coincides substantially with the axis32 of the pivotal support for the brush holder. With this construction,the curved contact face 34 of the brush element In remains substantiallythe same for all conditions of wear of the brush ID, This also minimizesthe tendency for the brush ill to toe or heel with different directionsof rotation of the current collector ll. It is desirable that thepressure on the brush element In should be substantially the same forboth directions of rotation in order further to minimize the tendency totoe or heel under different directions of rotation of the currentcollector ll. Ihis uniform pressure can be further assured by arrangingthe points of engagement of the elements 2| with the metal sheath l5nearer to the lower point of engagement 23 than to the upper point ofengagement 22 of the plate l9. With this type construction, a pigtailconnection can be made directly to the brush holder, if desired, or tothe metal sheath l5, and the simple brush member construction minimizesbreakage of these member which occurs with conventional constructionsusing screws or other pressure devices for securing the brush members tothe brush holders.

In Figs. 3, 4, and 5, I have shown another embodiment of my inventionwherein a brush memher is provided having a graphitic contact elementwith curved opposite sides 36 and 31 formed on substantially the samecenter of curvature. A metal sheath or cap 38 is secured to the upperend of the contact element 35 by a pair of rivets 39 and a pigtail 40 issecured to the cap 38 and adapted to provide an electrical connection toa suitable source of electrical power supply. The brush member isadapted to be biased towards a current collector 4| by a brush holder inwhich it is rigidly secured without the use of screws or similarpressure clamping devices. This brush holder includes a pair of elementsadapted to engage opposite sides of the brush member at spaced apartpoints for holding the brush in the brush holder. One of these elementsis formed as a sheet metal stamping having a side 42 with an enlargedpivotal supporting opening 43 in an end thereof integrally formed with atransverse face portion 44 and an opposite side portion 45. The faceportion 44 is formed with a pair of transversely spaced apart inwardlyprojecting brush engaging sections 45 which are adapted to engage theouter curved side of the brush member cap 38 which extends over the side31 of the brush contact element and is also formed with inturned endtabs 41 at the upper edge thereof which are arranged to engage the uppersurface 48 of the brush member cap 38. The brush member is adapted to beheld in the brush holder between the engaging sections 46 and anotherelement formed of a sheet metal stamping having a transverse plateportion 49 with a brush engaging section 59 which extends longitudinallyof the brush and projects outwardly from the plate 49 to engage theinner curved side of the brush cap 38 over the curved brush side 36 at apoint transversely intermediate the point of engagement of the brushholder sections 46 and the brush for wedging the brush member betweenthe engaging elements on the opposite sides thereof. The plate 49 isarranged between sides 51 and pivotally supported by a pivot pin 52which extends through openings 53 in the sides 5| and also through theopening 43 of the side 42 of the other brush holder element. The twobrush holder elements are connected together for guided limited relativemovement by a pin 54 which extends through openings 55 formed in thesides 5| of one brush holder element and through slots 56 formed in thesides 42 and 45 of the other brush holder element. The slots 56 extendangularly relatively to a line drawn between the holes 53 and 55 in thesides 5| of the other brush holder element such that relative pivotalmovement between the two elements causes their brush engaging surfaces46 and 58 to move toward or away from each other. In order to providefor this relative movement, the opening 43 in the side 42 of one of theelements is formed larger than the pivotal supporting pin 52. The brushengaging surfaces of the two elements are adapted to be biased towardeach other and the brush and brush holder biased toward the currentcollector 4| by a resilient coil spring 5'? arranged about the pivot pin52 and provided with an end portion 58 hooked over a stationary pin 59and another end portion thereof arranged in engagement with an upperplate portion BI and a tab 62 extending between the sides 51 of theouter brush holder element. As in the construction shown in Figs. 1 and2, the axis of the supporting pin 52 for the brush holder lies in aplane indicated by the line 63 substantially tangent to the center ofcontact between the brush member 35 and the current collector 4! toinsure substantially the same curvature of the brush contact face 64 forall conditions of wear of the brush element 35. With this arrangement,the biasing spring 51 provides for rigidly holding the brush member inthe brush holder by a Wedging action between the transversely spacedapart engaging surfaces of the sections 46 and 50 of the brush holderwith the cap 33 of the brush member and also for biasing of the brushholder and brush member as a unit towards the current collector M. Alifting tab is formed on the face 44 of the brush holder intermediatethe tabs 41 for raising the brush holder to replace or inspect the brushmember.

While I have illustrated and described par ticular embodiments of myinvention, modifications thereof will occur to those skilled in the art.I desire it to be understood, therefore, that my invention is not to belimited to the particular arrangements disclosed, and I intend in the appended claims to cover all modifications which do not depart from thespirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

l. A brush rigging for a brush member including means including apivo-tally supported brush holder having elements adapted to engage oneside of said brush adjacent opposite edges of said brush member attransversely spaced apart points for holding said brush member in saidbrush holder, means for engaging the opposite side of said brushintermediate said transversely spaced apart points, said last-mentionedmeans and said brush engaging elements of said brush holder and saidopposite sides of said brush member being arranged relatively to eachother to provide for wedging of said brush member between said engagingelements on opposite sides of said brush member, and resilient means forbiasing said brush holder and brush member as a unit toward a currentcollector and thereby increasing said wedging action between saidengaging elements and said brush member sides.

2. A brush rigging for a brush member including means including apivotally supported brush holder having elements adapted to engage oneside of said brush adjacent opposite edges of said brush member attransversely spaced apart points for holding said brush member in saidbrush holder, means for engaging the opposite side of said brushintermediate said transversely spaced apart points, said last-mentionedmeans and said brush engaging elements of said brush holder and saidopposite sides of said brush member being arranged relatively to eachother to provide for wedgin of said brush member between said engagingelements on opposite sides of said.

brush member, and means for biasing said brush holder and brush membertoward a current collector.

3. A brush rigging for a brush member including means including apivotally supported brush holder having elements adapted to engage oneside of said brush member at transversely spaced apart points and theopposite side of said brush member at longitudinally spaced apart pointsintermediate said first-mentioned points for h'olding said brush memberin said brush holder, said brush engaging elements of said brush holderand said opposite sides of said brush member being arranged relativelyto each other to provide for wedging of said brush member between saidengaging elements on opposite sides of said brush member, and means forbiasing said brush holder and said brush member toward a currentcollector.

4. A brush rigging for a brush member ineluding means including apivotally supported brush h'older having elements adapted to engage oneside of said brush member at transversely spaced apart points and theopposite side intermediate said first-mentioned points for holding saidbrush member in said brush holder, said brush engaging elements of saidbrush holder and said opposite sides of said brush member being arrangedrelatively to each other to provide for wedging of said brush memberbetween said engaging elements on opposite sides of said brush member,and resilient means for biasing said brush holder and brush as a unittoward a current collector and thereby increasing said wedging actionbetween said engaging elements and said brush member sides.

5. A brush rigging for a brush member including means including apivotally supported brush holder having elements adapted to engageopposite sides of said brush member at transversely and longitudinallyspaced apart points for holding said brush member in said brush holder,said brush engaging elements of said brush holder and said oppositesides of said brush member being arranged relatively to each other toprovide for wedging of said brush member between said engaging elementson opposite sides of said brush member, and resilient spring means forbiasing said brush holder and said brush member toward a currentcollector and thereby increasing said wedging action between saidengaging elements and said brush member sides.

6. A brush rigging for a brush member including means including apivotally supported brush holder having an element with a pair ofprojecting engaging sections adapted to enga e one side of said brush attransversely spaced apart points, a second element pivotally supportedrelatively to said first-mentioned element having a projecting engagingsection adapted to engage the opposite side of said brush memberintermediate said first-mentioned points, means for connecting togethersaid brush engaging elements of said brush holder for guided relativemovement for providing for varying the distance between said projectingengaging sections for wedging of said brush member between said engagingelements on opposite sides of said brush member, and means for biasingsaid second element relatively to said firstmentioned element intowedging engagement with said brush member.

7. A brush rigging for a dynamo-electric machine including a brushmember, means including a pivotally supported brush holder havingelements adapted to engage one side of said brush member at transverselyspaced apart points and the opposite side of said brush member atlongitudinally spaced apart points intermediate said first-mentionedpoints for holding said brush member in said brush holder with a currentcollector contact portion of said brush member projecting from one sideof said brush holder, said transversely spaced points being arrangednearer one of said longitudinally spaced points adjacent said brushprojecting side of said brush holder to provide substantially equalpressure on said brush member for both directions of rotation of thedynamo-electric machine, and means for biasing said brush holder andsaid brush member toward a current collector.

8. A brush rigging for a brush member including means including apivotally supported brush holder having elements adapted to engage oneside of said brush member at transversely spaced apart'points and theopposite side of said brush member at longitudinally spaced apart pointsintermediate said first-mentioned points and spaced longitudinalltherefrom for holding said brush member in said brush holder with acurrent collector contact portion of said brush member projecting fromone side of said brush holder, said brush engaging elements of saidbrush holder and said opposite sides of said brush member being arrangedrelatively to each other to provide for wedging of said brush memberbetween said engaging elements on opposite sides of said brush member,and resilient spring means for biasing said brush holder and said brushmember toward a current collector and thereby increasing said wedgingaction between said engaging elements and said brush member sides.

9. A brush rigging for a brush member including means including apivotally supported brush holder having elements adapted to engage oneside of said brush adjacent opposite edges of said brush member atspaced apart points for holding said brush member in said brush holder,means for engaging the opposite side of said brush intermediate saidtransversely spaced apart points, said last-mentioned means and saidbrush engaging elements of said brush holder and said opposite sides ofsaid brush member being arranged relatively to each other to provide forwedging of said brush member between said engaging elements on oppositesides of said brush member, resilient means for biasing said brushholder and brush member as a unit toward a current collector and therebyincreasing said wedging action between said engaging elements and saidbrush member sides, and means having the center line thereof in a planetangent to the current collector at substantially the center of thecontact of said brush member and the current collector for pivotallysupporting said brush holder.

10. A brush rigging for a brush member including means including apivotally supported brush holder having an element with a pair ofprojecting engaging sections adapted to engage one side of said brush attransversely spaced apart points and elements arranged to engage the topof the brush member, a second element pivotally supported relatively tosaid first-mentioned element having a projecting engaging sectionadapted to engage the opposite side of said brush member intermediatesaid first-mentioned points for holding said brush member in said brushholder, means for connecting together said brush engaging elements ofsaid brush holder for guided limited relative movement for providing forvarying the distance between said projecting engaging sections forwedging of said brush member between said engaging elements on oppositesides of said brush member, and resilient means for biasing said secondelement relatively to said first-mentioned element into wedgingengagement with said brush member and for biasing said brush holder andbrush member as a unit toward a current collector and thereby increasingsaid wedging action between said engaging elements and said brush membersides.

11. A brush rigging for a dynamo-electric machine including a brushmember, means including a pivotally supported brush holder havingelements adapted to engage one side of said brush member at transverselyspaced apart points and the opposite side of said brush member atlongitudinall spaced apart points intermediate said first-mentionedpoints and spaced longitudinally therefrom for holding said brush memberin said brush holder with a current collector contact portion of saidbrush member projecting from one side of said brush holder, saidtransversely spaced points being arranged nearer one of saidlongitudinally spaced points adjacent said brush projecting side of saidbrush holder to provide substantially equal pressure on said brushmemher for both directions of rotation of the dynamoelectric machine,said brush engaging elements of said brush holder and said oppositesides of said brush member being arranged relatively to each other toprovide for wedging of said brush member between said engaging elementson opposite sides of said brush member, and resilient spring means forbiasing said brush holder and said brush member toward a currentcollector and thereby increasing said Wedglng action between saidengaging elements and said brush member sides.

WAYNE J. MORRILL.

